[Self-Adhesive] The sound-proof foam panel has a self-adhesive tab covering the entire back that can stick to any surface. No tools or materials are needed for installation. Easy to shape and cut to size, altering 't affect performance. [Professional Sound Absorbing Properties] Acoustic foam panels are installed to reduce noise pollution.They effectively reduce reverb, flutter echoes, undesirable acoustic reflections, unwanted noises. Acoustic foam panels are used to control the reverberation sounds make and this is quite different from soundproofing. it can eliminate the in the room, the sound quality and stereo imaging. [Easy to Install]The sound-proof foam are compressed under vacuum during transportation and quickly to normal size by placing in a ventilated place for about 24-72 hours.If some acoustic foams have not been restored, You only need to dry in water, and they will expand completely, ( ventilate to dry for 24-48 hours install, then water will not hurt the adhesive). [High-Density -Retardant Material]The soundproof wall panels made up of High-density polyurethane foam at 50/lbs per yard. 2 inches thick, 25% more dense than competing products. It can moderate sound control on walls or ceilings. With professional sound suppression and noise reduction, the acoustic panel can the undesirable noise, Useful sounds are clearer.The sound-proof foam is fire retardant, stop fire from spreading. Keep you safe. [Wide Use] Acoustic Foam Panels is suitable for sound processing in occasions. Great for spot treating sound on walls in your studio or office, Recording Studios, Control Rooms, Offices Home Studios, Home Offices, Home Entertainment Theaters, conference rooms. Colour:gray Material:Polyurethane Size:30 x 30 x 5cm Package Contents: 12 * Acoustic Foam Panels(With adhesive, the color of the adhesive is random, and the specified color is not accepted) Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.